Hitherto, to monitor and control various industrial devices, apparatuses, etc. located in a plurality of remote positions and to collect data measured using various measuring instruments, including electronic meters, it has been required to issue commands from a monitoring/-control center or a data collection center to instruct an industrial personal computer or general computer, which functions as a server computer installed in each site and operates in accordance with programs described in a special assembly language or the C language, to collect monitored/controlled data and to execute a control program for control of the controlled target device, etc., and to transmit the result of device operation, the monitored measurement data, etc. to the monitoring/-control center through radio wirelessly or via public telephone lines or dedicated lines.
In such a case, the monitoring/control center has issued commands to or has received data, etc. from the personal computers or the general computers, or the various measuring instruments installed in the plurality of remote positions through individual communications using radio or telephone connection each time an occasion requires.
Therefore, a system must have been constructed by resorting to specialized makers, expert persons, etc., who are well skilled in communication protocols and control programs, and software such as dedicated programs must have been developed. Those situations have resulted in a higher system price, a lower transmission rate of commands, data, etc., and an increased communication cost.